Head lice infestations affect an estimated 6 – 12 million people every year worldwide, with most victims being young children. All hair types are equally effected. Contrary to popular belief, head lice infestations are not statistically more likely to occur in underdeveloped or impoverished communities, nor are they more likely in occur among certain hair types. All hair types are equally affected, and head lice actually prefer clean hair and scalps since it provides a much better environment for them to extract a blood meal from their host.

Body lice infestations, however, are more likely found in areas or communities with inadequate laundering of clothing and/or crowded areas where physical contact is more likely. Populations of homeless or displaced people often experience exceptionally high levels of body lice infestation but not head lice infestation.

Pubic lice infestations occur more often in sexually active individuals, especially if they have multiple partners.